Manufacturing Method of Waterproof Coil Zipper

ABSTRACT

a manufacturing method of waterproof coil zipper includes preparing a coil zipper, extruding a melted polymer material to fill a gap between two teeth sets and an interspace between two tapes, and to cover surfaces of the two tapes, cooling the polymer material to integrally form an anti-permeating body filled in the gap and a waterproof layer covering the surfaces of the two tapes, and cutting the anti-permeating body by a cutting tool. Accordingly, complex steps and low efficiency in manufacture caused by conventional manufacturing method are thus improved.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to a manufacturing method of zipper; and, more particularly, it relates to a manufacturing method of waterproof coil zipper able to avoid permeation in a fastened state.

2. Description of the Related Art

Zippers are daily used tools for modern lives. Many products such as clothes, bags, shoes are able to be opened or closed fast by using zippers, which surely improve the convenience of our lives. However, in order to broaden the use of zippers, a requirement in “waterproof zipper” able to be watertight when in a fastened state is gradually raised since the above said products are sometimes used outside in a rainy or windy environment. Thus, inventions of nylon waterproof zipper are gradually proposed.

The above zippers may be plastic zippers, metal zippers, coil zippers, etc. The coil zippers can be categorized as nylon zippers or polyester zippers according to different material used.

Early nylon waterproof zippers provide the waterproof function through applying a water repellent coating to the tapes of a nylon zipper. Unfortunately, this kind of conventional nylon waterproof zippers cannot provide a wholly watertight performance when fastened since water may permeate through a fastened zipper via the gap between its engaged teeth. Besides, the water repellent coating may flake off the tapes after a period of time. The above reasons both worsen permeation of the nylon waterproof zippers.

Accordingly, an improvement of nylon waterproof zippers is proposed, which is shown in FIGS. 1 and 2, labeled as “9,” and is manufactured by the following steps. First, two tapes 91 are engaged by two sets of teeth 92 respectively connecting with said two tapes 91. Second, a melted polymer elastomer material is applied to the engaged sets of teeth 92 and permeates into the gap between the teeth 92, so as to form an elastomer body 93 once the melted polymer elastomer material is solidified. Third, a waterproof film 94 is formed on and covers the two tapes 91 and the two sets of teeth 92 by either drying water repellant coated thereon or applying an adhered waterproof film thereon. Finally, a cutting step is performed to simultaneously cut a combination of the elastomer body 93 and the waterproof film 94 into two parts for the two sets of teeth 92 to be separated when unfastened. Through the above steps, the produced nylon waterproof zipper 9 not only is able to prevent the tapes 91 from the wet by the waterproof film 94, but also efficiently lowers the permeation due to the gaps between the teeth 92 via the elastomer body 93, so that the watertight performance of the nylon waterproof zipper 9 is largely improved.

However, since the elastomer body 93 and waterproof film 94 are formed by two separate steps, the above manufacturing method is not efficient enough. Moreover, the waterproof film 94 can flake off the elastomer body 93 because there is a combining junction between the elastomer body 93 and waterproof film 94 since they are not integrally formed, and thus the watertight performance of the nylon waterproof zipper 9 may reduce as time goes by.

As a result, it is necessary to improve the conventional nylon waterproof zipper.

SUMMARY OF THE INVENTION

It is therefore the objective of this invention to provide a manufacturing method of waterproof coil zipper forming an anti-permeating body and a waterproof layer simultaneously, so as to simplify the manufacturing steps and to increase manufacturing efficiency.

Another objective of this invention is to provide a manufacturing method of waterproof coil zipper that integrally forms the anti-permeating body and waterproof layer, so as to ensure a combination of these two members and to prolong lifetime of the produced waterproof coil zipper.

One embodiment of the invention comprises: preparing a coil zipper including two tapes and two teeth sets, wherein the two tapes are spaced from each other to define an interspace therebetween, wherein each of the tapes has a first surface and a second surface opposite to the first surface, the second surface of each of the tapes connects with a respective one of the two teeth sets, and the two teeth sets engage with each other; extruding a melted polymer material to fill a gap between the two teeth sets and the interspace between the two tapes, and to cover the first surfaces of the two tapes; cooling the polymer material to integrally form an anti-permeating body and a first waterproof layer, wherein the anti-permeating body is filled in the gap between the two engaged teeth sets, and the first waterproof layer covers the first surfaces of the two tapes; and cutting the anti-permeating body by a cutting tool.

In a preferred form shown, cutting the anti-permeating body further comprises cutting the anti-permeating body along a longitudinal center plane of a combination of the engaged teeth sets.

In a preferred form shown, the manufacturing method further comprises applying an adhesive to the first surfaces of the two tapes before extruding the melted polymer material.

In a preferred form shown, extruding the melted polymer material further comprises covering the second surfaces of the two tapes by the melted polymer material, and cooling the polymer material further comprises forming a second waterproof layer on the second surface.

In a preferred form shown, the manufacturing method further comprises applying an adhesive to the second surfaces of the two tapes before extruding the melted polymer material.

In the preferred form shown, preparing the coil zipper further comprises spacing two opposite third surfaces of the tapes by a predetermined distance, with each of the third surfaces linking the first and second surfaces of a respective one of the two tapes.

In the preferred form shown, each of the two tapes further comprises a fourth surface opposite to the third surface thereof. Based on this, extruding the melted polymer material further comprises covering the fourth surface of one of the two tapes by the melted polymer material, and cooling the polymer material further comprises forming a third waterproof layer on the fourth surface of the one of the two tapes.

In the preferred form shown, the manufacturing method further comprises applying an adhesive to the fourth surface of the one of the two tapes before extruding the melted polymer material.

In the preferred form shown, each of the two tapes further comprises a fourth surface opposite to the third surface thereof. Based on this, extruding the melted polymer material further comprises covering the fourth surfaces of both of the two tapes by the melted polymer material, and cooling the polymer material further comprises forming a third waterproof layer on each of the fourth surfaces.

In the preferred form shown, the manufacturing method further comprises applying an adhesive to the fourth surfaces of both of the two tapes before extruding the melted polymer material.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from the detailed description given hereinafter and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:

FIG. 1 is a sketch diagram showing a polymer-applying step of a conventional manufacturing method of waterproof coil zipper.

FIG. 2 is a cross-sectional sketch diagram of a conventional waterproof coil zipper.

FIG. 3 is a sketch diagram showing a polymer-extruding step of a preferred embodiment of the invention.

FIG. 4 is a cross-sectional sketch diagram of a workpiece of the preferred embodiment of the invention before cutting an anti-permeating body.

FIG. 5 is a cross-sectional sketch diagram of a product of the preferred embodiment of the invention after cutting the anti-permeating body.

FIG. 6 is a cross-sectional sketch diagram of a product of another preferred embodiment of the invention after forming a second waterproof layer.

FIG. 7 is a cross-sectional sketch diagram of a product of further another preferred embodiment of the invention with applying an adhesive to first and second surfaces.

FIG. 8 is a cross-sectional sketch diagram of a product of a further embodiment of the invention after forming a third waterproof layer.

FIG. 9 is a partial, enlarged view of the product in FIG. 8, showing the detailed arrangement of first, second and third waterproof layers with respect to the adhesive.

In the various figures of the drawings, the same numerals designate the same or similar parts. Furthermore, when the term “first,” “second,” “third” and similar terms are used hereinafter, it should be understood that these terms refer only to the structure shown in the drawings as it would appear to a person viewing the drawings, and are utilized only to facilitate describing the invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 3 through 5, a preferred embodiment of a manufacturing method of waterproof coil zipper of the present invention, which will be further illustrated as the following, is shown.

Referring to FIGS. 3 and 4, the first step is preparing a coil zipper (nylon or polyester zipper), with the coil zipper including two tapes 1 and two teeth sets 2. The two tapes 1 are spaced from each other to define an interspace therebetween. The tape 1 has a first surface 1 a, a second surface 1 b opposite to the first surface 1 a, and a third surface 1 c linking the first and second surfaces 1 a, 1 b. Each of the teeth sets 2 connects to the second surface 1 b of a respective one of the tapes 1, and the two teeth sets 2 engage but are able to be unfastened with each other. Specifically, the third surfaces 1 c of the two tapes 1 face each other while the two teeth sets 2 engage, and said two third surfaces 1 c are spaced from each other by a predetermined distance. Thus, a junction of the teeth sets 2 is exposed between the first surfaces 1 a of the two tapes 1 when the teeth sets 2 are engaged with each other.

The second step is extruding a melted polymer material to fill a gap between the two engaged teeth sets 2 and the interspace between the two tapes 1, and also to cover the first surfaces 1 a of the two tapes 1. In this embodiment, the melted polymer material is applied to a side of the coil zipper, which has the first surfaces 1 a, for the polymer material to permeate into the said gap and to cover the first surfaces 1 a. Preferably, the polymer material is Thermoplastic polyurethanes (TPU) or the likes of TPU, which can attach to cloth or leather with a high stickiness. Continuously, with cooling of the polymer material, the polymer material forms two parts: an anti-permeating body 3 and a first waterproof layer 4, which are integrally formed and connected, with said anti-permeating body 3 filled in the gap between the two engaged teeth sets 2, and with said first waterproof layer 4 covering the first surfaces 1 a of the two tapes 1.

Finally, cutting the anti-permeating body 3 along a longitudinal center plane of the combination of the engaged teeth sets 2 by a cutting tool “K,” which approaches the anti-permeating body 3 from a side of the coil zipper where the first surfaces 1 a locates, is performed. As a result, the two teeth sets 2 are able to be unfastened again but the coil zipper is watertight now when said teeth sets 2 engage, and, namely, a waterproof coil zipper is provided.

Specifically, when the manufactured waterproof coil zipper is in a fastened state in which said teeth sets 2 are engaged with each other, not only the first waterproof layer 4 is able to prevent the tapes 1 from the wet, but also the anti-permeating body 3 can avoid any liquid passing through said waterproof coil zipper via the gap between the two teeth sets 2. Besides, the combination between the anti-permeating body 3 and first waterproof layer 4 is surely improved since they are formed integrally. Therefore, a wholly watertight performance can be provided for a long time period. Furthermore, instead of connecting a waterproof zipper with cloth or leather by sewing that results in pinholes significantly lowering watertight performance, the polymer material forming the first waterproof layer 4 can be used to seamlessly connect the manufactured waterproof coil zipper with cloth or leather in a hot-melt-adhesion manner, so as to achieve an improved watertight performance.

Referring to FIG. 6, in another embodiment of this invention, there can be an additional step further applying said polymer material to the second surface 1 b of each tape 1 to form a second waterproof layer 5 covering the second surfaces 1 b. Alternatively, applying the melted polymer material to form this second waterproof layer 5 can also be performed in the step wherein the melted polymer material is extruded to fill the gap between the two engaged teeth sets 2 and to cover the first surfaces 1 a of the two tapes 1, so as to form the anti-permeating body 3, the first waterproof layer 4, and the second waterproof layer 5 at the same time. As a result, the manufactured waterproof coil zipper can provide a dual side watertight performance and thus is suitable for reversible products such as reversible jackets. Besides, the second waterproof layer 5 can also enhance the seamless connection between the waterproof coil zipper and cloth or leather.

Referring to FIG. 7, there can also be a step applying an adhesive 6 to the first surfaces 1 a or the second surfaces 1 b before extruding the melted polymer material to cover the first surfaces 1 a or the second surfaces 1 b, so as to enhance the combination between the tapes 1 and the first waterproof layer 4 or the second waterproof layer 5.

Referring to FIG. 8, in a further embodiment of the invention, each tape 1 may further comprise a fourth surface 1 d opposite to the third surface 1 c thereof. The fourth surface 1 d also links the first and second surfaces 1 a, 1 b. Based on this, said polymer material may be applied to the fourth surface 1 d of the tape 1 to form a third waterproof layer 7 covering the fourth surface 1 d. The third waterproof layer 7 may be integrally formed with the first and second waterproof layers 4, 5 in extrusion molding. Similarly, there can also be another step applying the adhesive 6 to the fourth surface 1 d before extruding the melted polymer material to cover the fourth surface 1 d, so as to enhance the combination between the tapes 1 and the third waterproof layer 7.

FIG. 9 is a partial, enlarged view of the coil zipper in FIG. 8, showing the detailed arrangement between the first, second and third waterproof layers 4, 5, 7 and the adhesive 6.

In sum, with the above illustrated embodiments of the manufacturing method of waterproof coil zipper, the anti-permeating body 3 and the first waterproof layer 4 can be formed simultaneously in the same step, and thus the manufacturing steps for the waterproof coil zipper are simplified to shorten the manufacturing cycle time, lower the manufacturing cost, increase the manufacturing efficiency, and prolong the lifetime of products.

Although the invention has been described in detail with reference to its presently preferable embodiments, it will be understood by one of ordinary skill in the art that various modifications can be made without departing from the spirit and the scope of the invention, as set forth in the appended claims. 

What is claimed is:
 1. A manufacturing method of waterproof coil zipper, comprising: preparing a coil zipper including two tapes and two teeth sets, wherein the two tapes are spaced from each other to define an interspace therebetween, wherein each of the two tapes has a first surface and a second surface opposite to the first surface, the second surface of each of the two tapes connects with a respective one of the two teeth sets, and the two teeth sets engage with each other; extruding a melted polymer material to fill a gap between the two teeth sets and the interspace between the two tapes, and to cover the first surfaces of the two tapes; cooling the polymer material to integrally form an anti-permeating body and a first waterproof layer, wherein the anti-permeating body is filled in the gap between the two engaged teeth sets, and the first waterproof layer covers the first surfaces of the two tapes; and cutting the anti-permeating body by a cutting tool.
 2. The manufacturing method of waterproof coil zipper as claimed in claim 1, wherein cutting the anti-permeating body further comprises cutting the anti-permeating body along a longitudinal center plane of a combination of the engaged teeth sets.
 3. The manufacturing method of waterproof coil zipper as claimed in claim 1, further comprising applying an adhesive to the first surfaces of the two tapes before extruding the melted polymer material.
 4. The manufacturing method of waterproof coil zipper as claimed in claim 1, wherein extruding the melted polymer material further comprises covering the second surfaces of the two tapes by the melted polymer material, and cooling the polymer material further comprises forming a second waterproof layer on the second surface.
 5. The manufacturing method of waterproof coil zipper as claimed in claim 4, further comprising applying an adhesive to the second surfaces of the two tapes before extruding the melted polymer material.
 6. The manufacturing method of waterproof coil zipper as claimed in claim 3, wherein extruding the melted polymer material further comprises covering the second surfaces of the two tapes by the melted polymer material, and cooling the polymer material further comprises forming a second waterproof layer on the second surface.
 7. The manufacturing method of waterproof coil zipper as claimed in claim 6, further comprising applying an adhesive to the second surfaces of the two tapes before extruding the melted polymer material.
 8. The manufacturing method of waterproof coil zipper as claimed in claim 1, wherein preparing the coil zipper further comprises spacing two opposite third surfaces of the two tapes from each other by a predetermined distance, with each of the third surfaces linking the first and second surfaces of a respective one of the two tapes.
 9. The manufacturing method of waterproof coil zipper as claimed in claim 3, wherein preparing the coil zipper further comprises spacing two opposite third surfaces of the two tapes from each other by a predetermined distance, with each of the third surfaces linking the first and second surfaces of a respective one of the two tapes.
 10. The manufacturing method of waterproof coil zipper as claimed in claim 4, wherein preparing the coil zipper further comprises spacing two opposite third surfaces of the two tapes from each other by a predetermined distance, with each of the third surfaces linking the first and second surfaces of a respective one of the two tapes.
 11. The manufacturing method of waterproof coil zipper as claimed in claim 10, wherein each of the two tapes further comprises a fourth surface opposite to the third surface thereof, wherein extruding the melted polymer material further comprises covering the fourth surface of one of the two tapes by the melted polymer material, and cooling the polymer material further comprises forming a third waterproof layer on the fourth surface of the one of the two tapes.
 12. The manufacturing method of waterproof coil zipper as claimed in claim 11, further comprising applying an adhesive to the fourth surface of the one of the two tapes before extruding the melted polymer material.
 13. The manufacturing method of waterproof coil zipper as claimed in claim 10, wherein each of the two tapes further comprises a fourth surface opposite to the third surface thereof, wherein extruding the melted polymer material further comprises covering the fourth surfaces of both of the two tapes by the melted polymer material, and cooling the polymer material further comprises forming a third waterproof layer on each of the fourth surfaces.
 14. The manufacturing method of waterproof coil zipper as claimed in claim 13, further comprising applying an adhesive to the fourth surfaces of both of the two tapes before extruding the melted polymer material. 